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Commitments and Contingencies - Restricted Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Long-term Purchase Commitment [Line Items]
Total long-term restricted investments	$ 34,453	$ 34,356
Workers’ compensation obligations
Long-term Purchase Commitment [Line Items]
Total long-term restricted investments	3,168	3,172
Reclamation-related obligations
Long-term Purchase Commitment [Line Items]
Total long-term restricted investments	27,268	27,238
Financial payments and other performance obligations
Long-term Purchase Commitment [Line Items]
Total long-term restricted investments	$ 4,017	$ 3,946

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Investments which are not defined as or included in marketable (debt, equity, or other) securities whose use is restricted in whole or in part, generally by contractual agreements or regulatory requirements. For use in an unclassified balance sheet.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 954
-SubTopic 210
-Name Accounting Standards Codification
-Section 45
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477220/954-210-45-4

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 954
-SubTopic 210
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478600/954-210-50-2

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